380 Bulletin American Museum of Natural History. [Vol. XXXVI, 



having the tail tipped with whitish, the color both above and below paler, the tail 

 and particularly bill, longer; differs from cinereiventris, its nearest geographic ally, 

 and agrees with torquatus in having no postocular spot. Wing, 56; tail, 30; tarsus, 

 24; culmen, 21.5 mm. 



Known only from the type-locality in the Magdalena Valley. 



(2049) Microbates collaris (Pelz.). 

 Rhamphocomus collaris Pelz., Orn. Bras., 1869, p. 84 (Marabitanas). 



A female from Florencia adds this species to the avifauna of Colombia. 

 Florencia, 1. , 



(2051) Cercomacra sclateri Hellm. 



Cercomacra sclateri Hellm., Nov. Zool., 1905, p. 288 (Chyavetas, e. Peru). 



I refer to this species, of which I have seen no authentic specimens, a 

 pair of birds from Florencia and a male from an altitude of 2000 ft., on the 

 mountain slopes above Florencia. 



Florencia, 3. 



(2053) Cercomacra tyrannina tyrannina (Scl.). 



Pyriglena tyrannina Scl., P. Z. S., 1855, pi. xcviii, p. 90 (Bogotd,). 

 Cercomacra tyrannina rufiventris Hellm., P. Z. S., 1911, p. 1165 (Boca de Calima; 

 Rio Calima; N6vita; Pueblo Rico). 



Inhabits the Tropical Zone of the greater part of Colombia. 



After a study of some thirty-four males and thirty-four females, in- 

 cluding topotypical series of tyrannina and crepera, I follow Ridgway (Bull. 

 U. S. N. M., 50, V, p. 95) in referring central and eastern Panama and Co- 

 lombian specimens to tyrannina. Cauca Valley specimens agree exactly 

 with those from the Bogota region, but males from southwestern Colombia 

 and western Ecuador average darker than true tyrannina but, on the whole, 

 are nearer to that form than to the blacker crepera. Females from Panama, 

 southwestern Colombia, and western Ecuador agree in the color of the 

 underparts and average deeper rufous than tyrannina but not so deep as 

 crepera. Above, however, they agree with the former rather than the 

 latter, crepera having the back and particularly tail, often with a rufescent 

 suffusion wanting in tyrannina. 



Barbacoas, 1 male, 3 females; Puerto Valdivia, 5; La Frijolera, 3; 

 Salencio, 1 male; Rio Frio, 1 male; Miraflores, 2 males; near Honda, 1 

 female; Buena Vista, 6 males, 3 females; Villavicencio, 3 males, 2 females. 



